Daily Archives: January 16, 2015

Dental Fluorosis Not Really That Bad, or is it?

This type of study is done every once and awhile and is intended prop up fluoridation to show that dental flourosis is not really that bad after all.  Cosmetic effects of fluoride (mottling of teeth) can occur in a portion of the population even at low fluoride levels in drinking water. Well, do the cosmetic effects from fluoride in drinking water negatively affect a child’s well being? That child will become an adult. Will it matter then?

Further, this and other studies typically infer that because the investigators did not find a problem using a particular statistical test that there is no problem. Such an inference is based certain assumptions that are not stated but are commonly assumed. It is simply not possible to prove a negative finding.

Moimaz SA, Saliba O, Marques LB, Garbin CA, Saliba NA. Dental fluorosis and its influence on children’s life. Braz Oral Res. 2015;29(1):1-7. doi: 10.1590/1807-3107BOR-2015.vol29.0014.

This study verified the prevalence of dental fluorosis in 12-year-old children and its association with different fluoride levels in the public water supply, and evaluated the level of perception of dental fluorosis by the studied children. To assess fluorosis prevalence, clinical examinations were performed and a structured instrument was used to evaluate the self-perception of fluorosis. The water supply source in the children’s area of residence since birth was used as the study criterion. In total, 496 children were included in the study. Fluorosis was diagnosed in 292 (58.9%) children; from these, 220 (44.4%) children were diagnosed with very mild fluorosis, 59 (11.9%) with mild fluorosis, 12 (2.4%) with moderate fluorosis, and 1 (0.2%) child with severe fluorosis. A significant association (p = 0.0004) was observed between the presence of fluorosis and areas with excessive fluoride in the water supply. Among the 292 children that showed fluorosis, 40% perceived the presence of spots in their teeth. The prevalence of fluorosis was slightly high, and the mildest levels were the most frequently observed. Although most of the children showed fluorosis to various degrees, the majority did not perceive these spots, suggesting that this alteration did not affect their quality of life.

Click here for article.

Urban Heat Island (UHI) Effect an Artifact of Data Tampering?

I really do not care to ask such questions as in the title of this post. But making arbitrary adjustments to data well-after the fact (e.g. here) is simply inappropriate and in my book qualifies as tampering (fraud) – Such action is simply counter to any ethical scientific practice. But as I tell my classes, not everyone is functioning out of the same rule book!

If there are factors that could have affected the original reported readings or there is some reason to think the measurements are inaccurate then add qualifying statements to the data set to provide a context for interpretation of the data. But don’t just arbitrarily change the numbers.

Think qualitative explanations, Not Quantitative Arbitrary Changes.